If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You will have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Building a Hot 250 x flow

Hi guys

Im thinking about building a hot 250 crossflow to swap the 400 od thousand kay one in the ute now, just wondering where to start? The car is a 1992 xf ute.

Would an E2 head change be worth wile, was thinking bit of a cam change 230/230 @ .50thou 520 valve lift , free flowing exhaust, compression bump up, flow up the intake a bit more, will a carbie change help also or just put a kit thru the standard weber? does it need head work or can i get away with stock ports and rockers etc. Only really looking to spend 1500 on it and after 150ish at the wheels.

Re: Building a Hot 250 x flow

Build it too hot and it'll be a pig to drive. Trade off a bit of power on the dyno and you'll have a smoother torquer 250 that'll still go hard. Do you mean 150rwhp or 150rwkw as you can get 150rwkw but it will not be as driveable as you would like me thinks. If you are chasing 150rwkw the weber although a great carb cannot flow this much it is maxed out at 130rwkw and restricting a bit even after 110rwkw etc. I'd go 86da block, EF crank (fully couterweighted), 200conrods (which are longer giving a better piston 2 rod ratio), flattops to suit, 'E2' head with 30thou shave, must run 98octane fuel only though and CR is around 11.3:1. Cam would probably need to be crow 2600-5500rpm etc. 4barrel redline manifold, 600holley would be good. Port match the redline to E2 and polish the exhaust side but not inlet as hinders fuel atomisation. Double row timing chain.

Re: Building a Hot 250 x flow

ive got a xflow which i put a "D" alloy head from a xf ute. i got it shaved 20thou and bolted it on.

then i got a 500 holley and redline manifold, and extractors and 2.5inch exhaust, and got it dyno tuned and jetted down to suit.

it came up with 110rwhp. remember this is a stock engine with stock cam and all i added was a bit of compression, and more airflow... and i get better fuel economy than before with a 500 holley!!!! (8.5l/100km on highway)

if i was you id do it cheap and easy like this:

1) flog off the weber and use a 350 or 450 or 500 holley, with a redline manifold

2) buy some extractors (mine cost $37.50 on ebay second hand!!!) and get a 2.25inch or 2.5inch exhaust.

3) search out a second hand engine with an alloy head in good nick ($200?)

4) put a decent midrange came in it...

5) while the heads off get it cracktested etc and shaved to give you 10:1 compression... (is that safe?)

youll get your 150rwhp on decent fuel...

i also changed to a celica fivespeed at the same time and it helped. those autos are so doggy... and maybe look at gettign rid of the fan and getting thermos...

personally i reckon that 110rwhp is pretty darn boring... i dont mind it but id much rather around 200rwhp. thats when things would get fun but then u start breaking things and dont get the economy that i get... i got a 3.5 diff in the garage - that would be alright...